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    <h2>ES6新增_let_const</h2>
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<script>
    //let和var区别

    // if(true) {
    //   let  a=10;
    //     console.log('1:',a)
    // }
   
    // console.log('2:',a)
    //let和const区别
    
    const b={
        name:'alice'
    }
    a=20

    console.log(b)
   b.name='hi'


   console.log(b)

   const fn=()=>{

   }

   const arr=[]
   arr.push(1111)

</script>
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